1. Field of the Invention
The present invention relates to an apparatus for containing and permitting transport of rod-shaped articles such as cigarettes and cigarette filter plugs. More particularly, the present invention relates to an apparatus for receiving filter plugs from a plug maker, for containing the plugs in a desired alignment and orientation while the tray is moved to a curing station, and for unloading plugs at a station for further processing.
2. State of the Art
In the manufacture of cigarettes and similar filtered smoking products, filter plugs are manufactured separately from the tobacco rod and loaded into trays for storage until needed for attaching to cigarette bodies. Storage can also permit a filter plug inventory to be established. Temporary storage may be necessary because the filter plug manufacturing unit can produce plugs at a higher temporary rate than the cigarette manufacturing operation will use them. In addition, temporary storage is frequently necessary to allow the bonding agents used in the filter plugs to cure before the filter plug is incorporated into the cigarette.
Typically, the filter plug manufacturing station includes a loading station for loading newly manufactured filter plugs into the storage trays. The cigarette manufacturing station will correspondingly include an unloading station to receive cured filter plugs from the trays. The use of storage trays allows the filter plugs to be contained in conveniently sized batches and easily moved from the filter loading station to a storage area and later to the unloading station.
Various container arrangements for filter plugs, cigarettes, and other rod-shaped articles are known in the art. For example, U.S. Pat. No. 4,201,507 to Hinchcliffe et al. discloses a mobile reservoir with a serpentine-shaped storage path and a conveyor which moves cigarettes from an entrance at one end of the serpentine-shaped path to an exit at the other end. U.S. Pat. No. 4,423,996 to Applegate et al. discloses a trolley with several vertical compartments each having a movable captive platform. Cigarettes are loaded by a conveyor into the compartments from the top and the platform descends to accommodate the size of the load. U.S. Pat. No. 4,507,040 to Baese et al. discloses a machine for transporting cigarettes from a making machine to a packing machine which includes moveable trays to accept an overflow of cigarettes. The trays include a movable bottom wall which lowers as the tray is filled; the tray is turned upside down to unload the cigarettes.
A problem in the prior art relates to the industry practice of handling filter plugs and other rod-shaped articles in bulk. Difficulties arise because plugs at the leading edges of the bulk flow tend to rotate out of the correct lengthwise alignment and foul the feeding and conveying mechanisms. This problem often occurs at the leading edge of the flow of plugs because the plugs in this area are loose and unconstrained, for example, by other plugs, by the conveyor, or by the walls of the tray. In addition, movement of the trays may cause plugs to spill from the tray because of the lack of containment.
Crossed or fouled plugs interrupt the transfer of plugs into and out of the trays causing delays in the manufacturing process. Jams in the feeding mechanisms also require the attention of an operator who must be on hand to correct the problem.
Another problem in the prior art is that the movable trays, particularly the type described above, can be complicated machines with many moving parts that are often expensive to manufacture and maintain.